What are you smoking? The median house price in London is 500k. At 750k you can afford 77% of houses and at a million you are in the top 10%. 50k per year is also a preposterously high expenditure. Rent will be your leading expense by probably a factor of 10. You could put aside 3k a month for rent (again, totally preposterous number) and not touch the sides.

The only thing I can think of that would even come close to making a difference is having children. Then all bets are off, they can cost as much as you like.